The present invention relates generally to a method of making a novel granulated product, and more particularly to a method of making a granulated product comprising a spherical shell and having a spherical space within it. More preferably, the present invention relates to a method of making a novel granulated ceramic product, especially a granulated ceramic product comprising a spherical shell and having a spherical (hollow) space within it. In the present disclosure, it is understood that by the term "granulated product" are intended various forms of products inclusive of granules, particles, tablets, pellets, clinkers, spheres, cubes, and beads.
So far, granulated products have applications in a wide range of industrial fields concerning pharmaceutics, fertilizers, foodstuffs, feeds, agriculture, catalysts, coloring materials, ceramics, powder metallurgy, detergents, cosmetics, plastics, and biotechnology.
Such granulated products have been manufactured by various methods such as tumbling granulation, compression granulation, agitation granulation, extrusion granulation, crushing granulation, fluidized bed granulation, melt cooling granulation, spray drying granulation, liquid phase granulation, vacuum freeze granulation, and in-liquid granulation.
With these granulation techniques, however, it is not easy to obtain granulated hollow products; only limited types of hollow products produced by dedicated granulation techniques represented by spray drying granulation are now available.
A primary object of the present invention is to provide a granulated product-making method that enables a hollow product having any desired, easily controllable particle size to be easily produced.